The Chemistry, Properties and Tests of Precious Stones

The Chemistry, Properties and Tests of Precious Stones by John Mastin: Unveiling the Science Behind Gems

John Mastin's "The Chemistry, Properties and Tests of Precious Stones" dives into the scientific world of gemstones, exploring their composition, characteristics, and identification methods. Here's a breakdown of the book's potential content:

Target Audience and Purpose:

• Likely aimed at gemologists, jewelers, or anyone interested in the scientific foundation behind gemstones.
• The book might serve as a comprehensive guide for understanding the chemical makeup, physical properties, and testing methods used to identify precious stones.

Content and Themes:

• Focuses on the chemistry of gemstones, potentially covering:

  • Mineral Classification: Explaining the different mineral groups that precious stones belong to (e.g., oxides, silicates).
  • Chemical Composition: Delving into the specific elements and compounds that make up various gemstones (e.g., diamond: carbon; ruby and sapphire: corundum with chromium impurities).
  • Color Formation: Discussing how the presence of certain elements or structural defects influences the color of gemstones.
  • Physical Properties: Exploring properties like hardness, refractive index, specific gravity, and their role in gemstone identification.

• Likely covers various methods for identifying and evaluating gemstones, potentially including:

  • Visual Examination: Observing color, luster, clarity, and cutting style.
  • Simple Tests: Using techniques like streak test (color of a mineral powder) or observing behavior under a loupe.
  • Advanced Techniques: Discussing the use of specialized instruments like refractometers (measuring refractive index) or spectroscopes (analyzing light absorption).

Historical Context:

• The publication date will determine the specific scientific understanding and testing methods discussed.
• Early 20th-century gemology might have relied less on sophisticated instruments compared to modern practices.

Overall Significance:

• "The Chemistry, Properties and Tests of Precious Stones" offers a valuable resource for understanding the scientific basis of gemstones.
• It highlights the connection between the chemical composition of a gem and its visual characteristics.
• The book serves as a historical reference for gemological practices and the evolution of gemstone identification techniques.